This page contains relief maps of the United States. The maps use false-color
3-D shading to show changes of altitude, somewhat as if you were viewing the
relief from a satellite. The maps are quite spectacular and very instructive;
if you study a part of the country that you thought you knew intimately, you'll
see all sorts of things you hadn't noticed before.

These are large area maps: three of them cover one third of the country
each (in 20 degree wide strips) and the fourth covers the entire country
(60 degrees wide by 25 degrees high). At full resolution, each
pixel corresponds to 30 seconds of arc (about half a mile in the
North-South direction). The heights are based on data that distinquishes 20
feet of elevation. I've included lower resolution versions too, as the high
resolution images are quite large files.

The images are based on digital elevation model (DEM) data from the USGS. The
USGS also offer free
programs for manipulating DEM and other data. See also the shaded maps
available at
USGS,
NOAA,
and Digital Wisdom (commercial). For
general maps, see the Perry-Castañeda
library map collection.